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\begin{document}
	
\PreviewEnvironment{tikzpicture}
	
\begin{figure}[htb] \centering
	\begin{center}
		\begin{tikzpicture}
		\draw[double distance=1.5mm] (-0.1,5) .. controls (-0.1, 4) and (-2.6,5) .. (-2.6, 3);
		\draw[double distance=1.5mm] (0.1,5) .. controls (0.1, 4) and (2.6,5) .. (2.6, 3);
		
		\foreach \n in {-2.5, -2.4, -2.3, -2.2, -2.1, -2, -1.9, -1.8 ,-1.7, -1.6,-1.5,-1.4,-1.3,-1.2, -1.1, -1, -0.9, -0.8, -0.7, -0.6, -0.5, -0.4, -0.3, -0.2, -0.1, 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5}{
			\draw (\n, 5.05)--(\n, 4.95);}
		\draw (-2.5,5)--(2.5, 5);
		\draw (-0,5)--(0, 5.2);
		
		\node at (0,6.1) {\scriptsize{Margin of victory in single-member district}};
		\node at (0,5.8) {\scriptsize{(Dual candidates only)}};
		\node at (-2.6,2.7) {\scriptsize{\textbf{Party-list seat}}};
		\node at (2.5,2.7) {\scriptsize{\textbf{District seat}}};
		
		\node at (1.1,4) {\tiny{$0<MV_i$}};
		\node at (-1.1,4) {\tiny{$MV_i<0$}};
		\node at (0,5.35) {\tiny{$MV_i=0$}};
		\node at (-2.55,5.15) {\tiny{$-1$}};
		\node at (2.55,5.15) {\tiny{$1$}};
		
		\end{tikzpicture}
	\end{center}
	\captionsetup{width=14cm,justification=centering}
	\caption{Dual candidates and the discontinuity in electoral mandate}
	\label{fig:DoubleInclusion}
\end{figure}

	
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